Abstract Blade vibration may trigger a self-induced aeroelastic instability (flutter). In turbomachinery choke flutter appears when a strong shock-wave chokes the blade passage. The aim of this study is to identify mechanisms responsible for the instability. An innovative methodology relying on the splitting of the emitter and receiver role of the blade is presented. It is successfully applied to 2D linearized RANS computations of choke flutter. The emission splitting shows that the vibration of the blades downstream of the shock-wave generates a backward traveling pressure wave triggering the aeroelastic instability. The reception splitting demonstrates the destabilising contribution of the shock-wave / separated boundary layer interaction. The source of flutter is finally a combination of inviscid (regressive waves) and viscous (unsteady separation) mechanisms.

中文翻译：

---

跨音速风扇二维扼流颤振触发机制的数值识别

摘要 叶片振动可能会引发自感应气动弹性不稳定性（颤振）。在涡轮机械中，当强烈的冲击波阻塞叶片通道时，就会出现阻风门颤动。本研究的目的是确定导致不稳定的机制。提出了一种依赖于叶片的发射器和接收器角色分离的创新方法。它成功地应用于扼流圈颤振的二维线性化 RANS 计算。发射分裂表明冲击波下游的叶片振动产生向后行进的压力波，从而触发气动弹性不稳定。接收分裂证明了冲击波/分离边界层相互作用的不稳定贡献。